validation of the positive and negative affect

Original Article http://dx.doi.org/10.1590/0104-07072016005610015

VALIDATION OF THE POSITIVE AND NEGATIVE AFFECT SCHEDULE IN PEOPLE WITH CHRONIC KIDNEY DISEASE

Luís Manuel Mota de Sousa1, Cristina Maria Alves Marques-Vieira2, Sandy Silva Pedro Severino3, Juan Luis Pozo Rosado4, Helena Maria Guerreiro José5

Doctoral student in Nursing. Nurse in Hospital Curry Cabral, Centro Hospitalar Lisboa Central EPE, Professor, Universidade New Atlântica. Lisboa, Portugal. E-mail: [email protected] 2 Doctoral student in Nursing. Professor, Universidade Católica Portuguesa. Lisboa, Portugal. E-mail: [email protected]. ucp.pt 3 M.Sc. in Health Management. Nurse in the Hospital Curry Cabral, Centro Hospitalar Lisboa Central EPE. Lisboa, Portugal. E-mail: [email protected] 4 Nurse, Hospital Fernando da Fonseca. Lisboa, Portugal. E-mail: [email protected] 5 Doctoral student in Nursing. Professor, Escola de Saúde Multipefil. Luanda, Angola. E-mail: [email protected] 1

ABSTRACT Aim: to analyze the psychometric properties of the Portuguese version of the Positive and Negative Affect Schedule scale in people with chronic kidney disease on hemodialysis. Method: this was a methodological study. A random sample of 171 people chronic kidney disease who receive hemodialysis in two clinics in the region of Lisbon, Portugal. Data was collected from May to June 2015. The psychometric properties were evaluated: Validity (construct, convergent and predictive), reliability (Cronbach’s α) and stability (test-retest). Results: showed that the Positive and Negative Affect Schedule scale has two distinct dimensions of positive and negative affect, reliable and stable both when obtained by interview or by questionnaire. Conclusion: the validity and reproducibility of the Portuguese version of the Positive and Negative Affect Schedule scale in people with chronic kidney disease are consistent with the original version and the English version of this scale. DESCRIPTORS: Emotion. Chronic renal insufficiency. Validation studies. Psychometrics. Nursing.

VALIDAÇÃO DA POSITIVE AND NEGATIVE AFFECT SCHEDULE EM PESSOAS COM DOENÇA RENAL CRÔNICA RESUMO Objetivo: analisar as propriedades psicométricas da versão portuguesa da escala Positive and Negative Affect Schedule em pessoas com doença renal crônica em programa de hemodiálise. Método: tratou-se de um estudo metodológico. A amostra randomizada foi constituída por 171 pessoas com doença renal crônica, submetidas a hemodiálise em duas clínicas na região de Lisboa, Portugal. Os dados foram coletados de maio a junho de 2015. Foram avaliadas as propriedades psicométricas: validade (construto, convergente e preditiva), confiabilidade (α de Cronbach) e estabilidade (teste-reteste). Resultados: Permitiram verificar que a escala Positive and Negative Affect Schedule apresenta duas dimensões distintas de afeto positivo e negativo, confiáveis e estáveis, obtidas por entrevista e por questionário. Conclusão: a validade e reprodutibilidade da versão portuguesa da escala Positive and Negative Affect Schedule em pessoas com doença renal crônica são consistentes com a versão original e a versão portuguesa desta escala. DESCRITORES: Emoções. Insuficiência renal crônica. Estudos de validação. Psicometria. Enfermagem.

Texto Contexto Enferm, 2016; 25(4):e5610015

2/8

Sousa LM, Marques-Vieira CMA, Severino SSP, Rosado JLP, José HMG

VALIDACIÓN DE LA POSITIVE AND NEGATIVE AFFECT SCHEDULE EN PERSONAS CON ENFERMEDAD RENAL CRÓNICA RESUMEN Objetivo: analizar las propiedades psicométricas de la versión portuguesa de la Escala Positive And Negative Affect Schedule en personas con enfermedad renal crónica en programa de hemodiálisis. Método: este estudio tiene carácter metodológico cuya muestra fue aleatoria y constituida por 171 personas con enfermedad renal crónica que realizan hemodiálisis en dos clínicas de la región de Lisboa. La recogida de datos se realizó entre Mayo y Junio de 2015. Se comprobaron las siguientes propiedades psicométricas: validez (constructo, convergente y predictiva), fiabilidad (α de Cronbach) y estabilidad (teste-reteste). Resultados: permitieron comprobar que la escala Positive and Negative Affect Schedule presenta dos dimensiones diferentes de afecto; el positivo y el negativo, y que estes se presentan fiables y estables tanto mediante la utilización de entrevista como de cuestionário. Conclusiones: la validez y reproductibilidad de la versión portuguesa de la escala Positive And Negative Affect Schedule en personas con enfermedad renal crónica son coincidentes con la versión original y portuguesa de la escala. DESCRIPTORES: Emociones. Insuficiencia renal crónica. Estudios de validación. Psicometría. Enfermería.

INTRODUCTION Chronic kidney disease (CKD) is a progressive and irreversible condition characterized by reduced renal function. It is categorized according to the glomerular filtration rate. Treatment depends on the evolution of the disease, which may be conservative, using drugs, the prescription of diets and fluid intake, or can be done with renal replacement therapies, which uses hemodialysis, peritoneal dialysis and kidney transplantation.1 This disease affects the patient’s renal function and causes physical, psychological and social changes.2 The symptoms presented by the patient with CKD include loss of physiological and biochemical functions; bone diseases; anemia; inability to maintain activities and family duties; loss of physical, cognitive and sexual competence; dependence on health care and hemodialysis machines, which can lead to social withdrawal.3 Despite treatment with renal replacement therapies, which allow the patient to prolong life and ensure their survival, there are disadvantages, in particular because it affects the performance of activities of daily life, the welfare, the occupation and the quality of life.3-4 Affect is an integral part of the patients, being necessary to promote it positively, to ensure well-being.5 The Positive and Negative Affect Schedule (PANAS) scale6 was developed in order to provide brief, easy to administer and valid measures to assess the positive and negative affects.7 PANAS measures the positive affect (PA) and negative affect (NA), which correspond to two general dimensions that describe the emotional experience of individuals. High NA is associated with unpleasantness and subjective to discomfort, which involves emotions like fear, nervousness and disturbance. High PA is associated

with pleasure and subjective to well-being, and covers the emotions like enthusiasm, inspiration and determination.6 The PANAS can be used as a measurement related to the affective dimension of the concept of subjective well-being,8 it has been validated in various cultures and in different languages including, English, German, Turkish, Estonian, Spanish, Russian, Japanese,9 in Portuguese7,9 European and Brazil,10 Indian,11 French and12 Pakistani and Hungarian.13 In the construct validity, the principal component analysis method (PCA)6-8,13 or maximum likelihood10 with varimax rotation6,10 and confirmatory factor analysis (CFA) was used.12,14 The correlation coefficient between the PANAS and anxiety, depression and stress,6 and subjective happiness and satisfaction with life in general was used in convergent validity.11 Cronbach’s α was used in the reliability6-7,10-13 and test-retest to assess stability.6 In the cultural adaptations, the results have shown good psychometric properties (construct validity, convergent and discriminant).9 However, it is important to consider that the semantic translation of emotions is not a univocal process, since there are emotions that can have several possible translations and others have a direct translation, but with multiple and distinct semantic content in different languages.7 There is evidence of the importance of subjective well-being in the social context and health, however, little has been explored in patients with CKD in the final stage.16 The PANAS scale is validated for the Portuguese population, but not in patients with CKD. Paying attention to the patient with CKD involves complex processes and is emotionally draining3-4 it must be verified that the PANAS scale allows


Validation of the positive and negative affect schedule in people...

3/8

negative and positive affect measurements and, is reliable and valid for this specific population. The main question of this research was the following: what are the psychometric properties of the PANAS scale in patients with CKD? In this sense, the aim of this study is to analyze the psychometric properties of the Portuguese version of the Positive and Negative Affect Schedule scale in people with chronic kidney disease on hemodialysis.

The PANAS6 scale was adapted and translated for the Portuguese population,7 and consists of two subscales: PA and NA, with ten items each, in which constructs are assessed on a Likert scale of 1 to 5. The respondents were asked to indicate the extent to which they each felt emotions (for each of the 20 items) at the present time. The PA dimension is much more present than the higher score, a maximum of 50 points. The study of the Portuguese version of PANAS revealed just as the original scale, the existence of two factors, internal consistency with Cronbach’s α of 0.86 (in the original, α=0.88) for the positive affection of scale 0.89 (in the original, α=0.87) for the negative affect scale and a correlation between the two factors of -0.10 (in the original, r=0.17).7 SHS18 consists of four items; in items two and three the participants were asked to self-characterize themselves compared to their peers in absolute and relative terms. Items one and four correspond to descriptions of happiness and unhappiness. The score of the last item is reversed. On this scale the respondents were asked to indicate the extent to of the statements in self-characterizing, and the answer is given in a visual analogue scale with seven positions, based on two antagonistic statements, which express the level of happiness or lack thereof. The Portuguese version features a single factor with an internal reliability with the value of Cronbach’s α of 0.76.16 The PWI has been developed from the Comprehensive Quality of Life Scale. It consists of seven items/areas (satisfaction with standard of living, health, personal development, personal relationships, sense of security, connection to the community, and security for the future) that aims to assess satisfaction with life in general. For each statement the respondents are asked to say how satisfied they are with each item/area on a scale from 0 (extremely dissatisfied) to 10 (very satisfied) with a neutral intermediate position. The PWI is calculated on a rating ranging from 0 to 100 (maximum percentage of the scale). The CFA of the English text revealed the existence of a single factor, with an internal reliability with the value of Cronbach’s α of 0.81.17 Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) version 20.0. In the evaluation of the psychometric properties, the study of reliability was performed using the Cronbach’s α. Additionally, a test-retest was used (after 48 to 96 hours in 40 randomly selected

METHOD A methodological study was performed,14 in two units of the Diaverum Dialysis Clinic in the Lisbon region, between May and June 2015. The population consists of patients with CKD on hemodialysis. The inclusion criteria were: patients with CKD on hemodialysis for at least six months, and to be 18 years of age or over. Exclusion criteria were: patients with cognitive impairment and active psychiatric illness. Information regarding these conditions of exclusion was obtained through the patient’s record. In total, 253 patients with CKD met the eligibility criteria (139 in Clinic 1 and 114 in the Clinic 2). The sample was composed of patients who met the eligibility criteria and their selection was done probabilistically (without random replacement, taking into account the eligibility criteria. The calculation of the sample, with a confidence interval (IC) of 95% and error sample of 5%,15 recommended a required sample of 192 patients (103 in the Clinic 1 and 89 in Clinic 2). Therefore a random selection without replacement was performed. However, of the patients with CKD selected in the Clinic 1, six patients refused, two were hospitalized and two dropped out, in Clinic 2, four refused to participate, two were admitted to hospital and five gave up. Complete data of 171 patients, 93 (89%) of Clinic 1 and 78 (88%) Clinic 2 were obtained at the end. The following instruments for data collection were used: positive and negative affectivity, the Portuguese version of PANAS,7 subjective happiness, the Portuguese version of the Subjective Happiness Scale (SHS),16 satisfaction with life in general (SWL), the Personal Wellbeing Index (PWI) was used17-01 which is a tool for the characterization of the sample profile for sociodemographic and clinical levels (age, gender, nationality, education, occupation, marital status, duration of dialysis, presence of hypertension and diabetes).


4/8

Sousa LM, Marques-Vieira CMA, Severino SSP, Rosado JLP, José HMG

patients, 26 questionnaires and 14 interviews) for the evaluation of the stability through the intraclass correlation coefficient (ICC) and the Spearman-Brown correlation.19 A minimum value of 0.70 was adopted as satisfactory internal consistency.19 In the validity study, EFA was the maximum likelihood method with Varimax rotation. The adequacy was assessed by Kaiser-Meyer-Olkin (KMO) and Bartlett’s test of sphericity. Convergent validity was assessed by Pearson correlation(r) between the PANAS, the SHS and the PWI. To check the discriminant validity the Student t for independent samples was used, or for ANOVA more than two independent samples was used. Categorical variables were expressed as percentages or absolute value and continuous variables as mean standard deviation or median. Median age and hemodialysis time were used as cut off points to create categorical variables. The significance level was set at p